Thursday, June 07, 2012

We are experimenting with a new feature of LC's Linked Data Service designed to more easily make use of the available data by providing a simple way to import the data into OWL ontologies, especially via OWL editors such as Protégé [1] or TopBraid Composer [2].

As you all know, we published a number of vocabularies and value lists - such as the MARC Lists for example - as MADS/RDF Authorities, SKOS Concepts, and RDF Resources quite some time ago.

Although the data made available (URIs, labels, etc) are useable in ontologies and OWL editors as is, our own use cases have led us to simplify the process of making use of them in ontologies and OWL editors. To this end, we've modified the output so that the data are readily understandable by an OWL editor (for example, we output rdfs:label for the label properties in addition to skos:prefLabel and madsrdf:authoritativeLabel because OWL editors appear pre-configured to understand rdfs:label and not necessarily skos:prefLabel) and we've created mini-ontologies designed for import into other ontologies. The idea is that the mini-ontology will import all that is needed to make use of the vocabularies and value lists in an user-friendly manner.

For example, to make use of the ISO639-2 Languages one could import the following ontology:

This will import all the ISO639-2 Language resources, and required data (such as labels and RDF types), and the ISO639-2 Language Class (also defined by LC). Once imported, you would then define an Object Property, the range of which is a resource that is an instance of an ISO639-2 Language (http://id.loc.gov/vocabulary/iso639-2/iso639-2_Language).